Bedroom Air Conditioning Upgrade

Our current bedroom air conditioning system, a 16 year old Mitsubishi Electric ducted system, has been starting to have difficulties. For example, it has simply been refusing to start until I disconnect it from power and then reconnect it again. With summer fast approaching it was decided that it would be best to replace it. Originally, I thought the obvious solution would be to replace it with an inverter ducted unit, however after doing some research, it became apparent that there were other options that required careful consideration.

More of the Same Problems

The biggest problem with installing another ducted unit is how the unit is used most of the time. Some of the upstairs rooms are used as bedrooms, while another two are used as work/study rooms. During the day there is often only the need to air condition one, or two of the rooms. With the current ducted system, it was all of the rooms or nothing. This was wasting a lot of energy by air conditioning rooms that never had anyone in them. The opposite would then be true during the night; The work rooms would be cooled or heated when there was no one in them.

This led me to consider zoning the upstairs ducts so that I could select to only have one or two rooms running. This presented a new problem. The larger inverter units, 10KW and above, are not able to reduce their cooling (or heating) capacity much below 5KW. If I were to try and just run this 5KW into one room, it would lead to rapid temperature fluctuations, which would be inefficient and uncomfortable.

What I Really Wanted

At this stage, I had managed to eliminate most of the ducted options. After some thinking, I determined that the new system would have the following requirements:

  • Each room could operate on its own
    • Essentially to cool or heat one room, none of the other rooms should be cooled or heated.
  • Each room should be able to select its own temperature
    • Different members of the family prefer different temperatures.
    • With the old system, it was difficult to find a temperature that everyone liked.

The Options

After browsing the websites of many big air conditioning companies, I realised there were two main options for meeting my requirements.

Multi-Split System

  • Allows multiple indoor units, in this case one per room, to be serviced by a single outdoor unit.
    • Each of the indoor units could be operated independently and be set at their own temperature.
  • Advantages
    • Allows the system to remain centralised (Only one power connection required)
    • Only requires the placement of one outdoor condensing unit
    • Considerably more efficient than the current Mitsubishi unit
  • Disadvantages
    • Lack of redundency
      • If anything went wrong with the one outdoor unit, all of the rooms would be without heating or cooling
    • Due to the large capacity of the outdoor unit, about 10KW, the inverter compressor was only capable of  reducing its output to about 2KW. If there was only one room turned on, this would result in the unit having to cycle on and off to maintain the temperature.
      • While this problem is considerably smaller than with another ducted system, it was still present.

Four Mini-Split Systems

  • Basically four completely independent systems
  • Advantages
    • The most efficient solution
      • For 10KW of cooling in total, I calculated the power usage to be only 1960 watts.
      • Nearly 2000 watts more efficient than the current system.
    • Redundancy
      • If a fault was to occur, it would only affect the one room that unit was servicing.
    • As the smaller units are designed for small rooms, the compressor is capable of reducing its capacity down to 0.9KW, allowing the air conditioner to maintain the room at a much steadier temperature.
    • Cost
      • Despite my first thought, the installation quote for four mini-split systems was actually less than the quote for one multi-split system.
    • Allowed for the use of the new industry refrigerant R-32.
  • Disadvantages
    • Requires the placement of four outdoor units
      • In my situation this is not really a problem as the units can be mounted on the walls outside the bedrooms.
    • Each unit requires its own power supply.


After careful consideration of all the numbers involved, I decided to go for the four mini-splits.


After considerable research online and consulting with HVAC professionals, I narrowed the selection down to either Daikin or Panasonic. Due to the number of Daikins operating perfectly in other locations around the house, I decided to go for the Daikins.

Furthermore, the Daikin units were also the most efficient. They only used 490 watts of electrical energy to provide 2500 watts of thermal cooling. That’s an efficiency factor of over five times.

After the HVAC professional had appropriately sized the units it was determined that would would install four Daikin Cora series units (FTXM25QVMA).


A few pictures of the installed units

One unit connected to the vacuum pump
Two of the outdoor units mounted near each other.
Outdoor unit data sheet
One of the indoor units
The remote controller

New Security System Server

The original server I was using for the security system is about three years old. Due to an underestimate on my behalf as to how much CPU time recording multiple cameras would take, it has also become underpowered for the application. Recently it has been running at about 90% CPU utilisation.

With the intention of adding a new camera sometime in the future, I decided it was time to upgrade the system.

The Design

This time I decided to build a custom server for the application. This allowed me to include everything I wanted. The hardware I eventually decided on was the following:

  • Intel Quad Core i5 (6th Generation)
    • This processor would have more than enough power to run the current setup and to allow for future expansion.
  • DDR4 RAM
    • As DDR4 RAM is becoming more mainstream now I thought it would be good to include.
    • As I intend to keep the system running for a long time I wanted to still be able to get parts in the future.
  • SSD
    • I decided to run the operating system off an SSD to make it faster and hopefully more reliable.
    • As the video recording would result in almost constant activity to the recording hard drive, I wanted to run the operating system off a different drive.
  • 2TB + Rotational Hard Drive
    • I didn’t want the videos to be recorded to the same drive as the operating system.
    • Instead I added a 2TB rotational drive to hold the recordings.
    • They are also mirrored to an external drive for redundancy.
  • Rack Mountable Case
    • To consume the least amount of space in my rack I decided the best case would be one that could be rack mountable.
    • I didn’t want to install a special cooling system, like some of the smaller 1U and 2U rack cases require.
      • I decided to go for a 3U rack case as it would allow be to use the stock CPU cooler and have room for full size PCIe cards.
  • High Quality Power Supply
    • As this server was going to be operational all of the time, a high quality power supply was essential.
  • Windows 10 Pro
    • Blue iris, which is used to control the cameras only runs on windows (Otherwise I would have used Linux)
    • I decided it was best to go with the latest version of Windows, being Windows 10
    • Finally I wanted access to Remote Desktop as the server would be running headless, therefore I required the professional edition.

Building the Computer

The case I purchased allowed sufficient room for the motherboard. However, the power supply I purchased was physically too large to fit into the case. The back of the power supply would hit the hard drive mount.

To solve this problem I removed the hard drive mount from its intended location. I then found that there was enough space below the power supply in the case to mount the hard drives. I had to cut off unnecessary parts of the bracket, but eventually was able to mount the hard drives to the bottom of the case, under the power supply.


Once I installed Windows, I had to reconfigure Blue Iris again. This was not too difficult as all of the devices have static IP addresses and they are all well documented. The task that took the most time was calibrating the camera’s motion detection settings.

Once the system was completly running I noted that the idle CPU utilisation was only 25%. This was a significant improvement from the old system, which was averaging 90%.

Cable Modem/Router/Switch

The security system had been running for a number of months and was performing well. I was about to go on holiday and was looking forward to testing the system remotely. As I went around the house to turn off some of the appliances that did not need to be running while I was away, it became apparent that I had a small design flaw with the system.

To access the system while on holiday, it would obviously require an internet connection. The problem was that the cable modem, that provides the house’s internet was located on the other side of the house, many switches downstream. To maintain the internet connection I would have to leave all of these switches powered on while on holiday.

I decided that the best solution was to move the cable modem into the box with the security system itself. This way the security system doesn’t need to rely on any hardware in the house to provide its link to the internet.

A Few Problems With The Idea

My first problem was that I would have to obtain coaxial cable, connectors and a crimping tool. This didn’t prove to be much of a problem as I could get all three of those at Jaycar.

Secondly, I didn’t want to change the house’s current  coaxial wiring put in by Optus, mainly for two reasons. I was not sure if they would take kindly to me tampering with their wiring and secondly I didn’t want them to know the location of my security box should I ever have problem with the cable modem. The solution was to create an ‘extension lead’ of coaxial cable which I could connect to the existing outlet in the house and run to my box. This would allow me to put the cable modem back in the original location should there ever be a problem.

Another problem was running the bulky and unbendable coaxial cable through the walls and floor. While this took a long time it was ultimately achievable.

Finally, the cable modem itself does not perform any routing or NAT functions. Up until now I had been using my wireless access point to perform the routing and NAT, however, there was no point putting the access point into the security box as it is located no where near the main living areas of the house. My solution was to get a dedicated router and place it into the security box as well.


The running of the coaxial cable itself did not prove to be too difficult, apart from feeding it up some of the walls.

Installing the Router

I purchased a router with two LAN interfaces. This allowed me to connect one interface to the main network and another interface to the security system network. The router would act as the default gateway to both networks as well as providing NAT and DHCP.

Once the router was installed I encountered the first major problem. As the router was directly connected to both the main network and the security system network, it would route traffic between them. This created a security vulnerability as I did not want anyone from the main network to be able to access the cameras, only the web server. The solution was to use contiguous IP addressing for all of the cameras and then write one access control list for the router to block access to this IP range. The web server was given an IP address out of the blocked range allowing it to still be accessed.

Installing a Switch

After the router was installed, I was now feeding both the main network and the security network from the box. This involved several small switches which was making the box very untidy.

My solution was to get a managed switch to switch the whole network and use VLANs to seperate the two networks. I ended up with a 24 port switch which I split down the middle. The first 12 ports were assigned to the first VLAN and connected devices from the main network. The next 12 were in a different VLAN and connected to the security system devices.

Unfortunately as this switch was an afterthought I didn’t get a router that supported router on a stick interVLAN routing. All this meant was that I needed two connection between the switch and the router; one for each VLAN.

All of the new devices installed. The exact models have been obscured for security.
All of the new devices installed. The exact models have been obscured for security.

Opening a Kodi Addon Through JSON Interface

For my home security system I wanted to be able to use my digital photo frame, running Kodi, to display a video feed of my front door whenever movement was detected.  To do this I needed my security system, Blue Iris, to send a JSON command to Kodi which would open a script to display the front door feed.

Displaying The Camera Feed

To display the camera feed I found a Kodi addon called Security Cam Overlay. This allowed me to put in my camera’s IP address and password and it would display the camera’s feed, in the corner of the Kodi window.

Getting Kodi To Open The Addon When Motion Is Detected

After some research, I found that Kodi could be asked to open addons via its JSON interface. The code to open the addon went as follows:


When this was sent to the Kodi box, the addon opened and displayed the camera feed.

The second part was to get the security system, powered by Blue Iris, to send the JSON command when motion was detected. Luckily Blue Iris has an option to request from a web server when motion is detected. I placed the JSON command above into the web server address and the whole process became automated. Blue Iris would detect motion and request from the web server. This executed the JSON command to open the camera overlay addon in kodi, which in turn would display a camera feed of the front door.

I selected the option to request from a web service when the camera was triggered.
I selected the option to request from a web service when the camera was triggered.
I then entered the JSON request as the server address and everything worked.

A Small Problem

After the system had been working for a few hours a problem started to emerge. To ensure that the front door camera captures all movement, it is quite sensitive to motion. This led to the camera stream being displayed on the photo frame every time a car came down the street. Ideally I would only like the camera stream to be displayed when there is actually someone at the front door. I intend to create some sort of Raspberry Pi powered doorbell to address this problem in the future.

Security System

I decided to build a security system for my house. At first I thought this would be a relatively simple project, a couple of sensors and a controller of some sort. However, when I actually started researching the topic, it became apparent how many different approaches I could take. This led to some complicated decisions before I could even begin to build the system.

Cameras Or Sensors

The original plan was to just create an alarm system using motion sensors to determine if there was any activity around the house. However, while researching I found that the price of IP cameras had dropped considerably. After researching a number of cameras I decided that I would base the system around IP cameras, instead of motion sensors.

Cloud or Local Recoding

Once I started researching cameras it became apparent that there were two main categories of network cameras, cloud based and local recording. The cloud based cameras were extremely locked down with very few user customisable  features. This would be okay if the software and apps that came with these cameras was of a high quality. Unfortunately after trying a number of prototypes, the majority appeared to be poorly designed and unreliable.

For some time I tried a Belkin cloud based camera. This was by far my favourite of the cameras as it had a high definition sensor and a very wide lens. Unfortunately the software it came with was so locked down that I could not integrate it with anything other than the app that it came with (which wasn’t very good). I even used Wireshark to monitor the traffic it sent over the network in the hope of being able to tap into the video stream. I did not succeed.

This was the Belkin cloud camera I tested.
This was the Belkin cloud camera I tested.

Having been disappointed with the performance of the Belkin camera I was not interested in any more cloud based cameras. Instead I decided to look at cameras that would allow me to record to one central location. While researching possibilities I came across the D-link range of network cameras. These cameras seemed to be of a higher quality then the others I had tried and also were very customisable to the users exact needs.

Having found cameras that seemed to satisfy my needs, I started looking to see if D-link had any devices that would allow me to record to a central location and trigger alerts when certain conditions were met.

D-Link NVR

After some looking I came across a D-Link device known as a NVR or Network Video Recorder. This device had the ability to record motion from all of the cameras and store it on internal hard drives. There were however a few problems with using this device. Firstly, it didn’t have any features that would allow me to trigger an alarm if motion was detected.  Secondly, the device itself cost $600 AUD which was too expensive if the device did not fulfill all of the requirements.

The D-Link NVR
The D-Link NVR

Software NVR

While trying to figure out whether I could make the D-Link NVR work for my situation I wondered if anyone had created NVR software for a computer. After researching NVR software I found Blue Iris ( which seemed to have many of the features I was looking for.

After more testing I decided that Blue Iris was ideal for my application as it had:

  • Different “profiles” that it could be put in for armed and disarmed.
  • An app allowing the cameras to be viewed remotely.
  • Compatibility for my chosen D-Link cameras.
  • An alarm function where it could actually sound an alarm using the audio output of a computer.
  • The ability to trigger numerous types of alerts when motion was detected.


Having found software that I could  use as my NVR the next step was to buy a computer that the software could run on. After looking around for some time at a variety of different computer systems I decided against a custom built machine and instead went for a reasonably powerful Lenovo workstation PC (M73). This PC had enough power to run the software even with several more cameras then I intended to use. It was also more efficient then the majority of other computers. The computer was a mini ATX form factor, meaning it would not take up too much space. Furthermore it had sufficient expansion slots for possibly adding a DIDO card or a second NIC in the future.

The Lenovo PC I Chose
The Lenovo PC I Used



Once all of the devices were running, I calculated the expected current draw of the whole system. I then purchased a UPS with a high enough capacity to keep the system running for several hours without mains power.

Putting It All Together

Now that I had all of the equipment it was now time to connect them all together.


The setup of the computer was simple. First, I performed a fresh install of windows to remove all of the useless software that Lenovo had placed on it. Then I installed Blue Iris and configured the settings I needed.


The hard part was running the Cat 6 twisted pair Ethernet cable from my hidden security box to the location for each camera. This ultimately required running cables underneath the house as well as through the walls and ceilings. Finally when all of that was complete I had to learn how to crimp the RJ-45 connectors on the cable.


The next step was to create another network, separate  from my home network for the security system to run on. To do this I purchased a router with an inbuilt 8 port switch. This allowed me to create another network and connect all of the cameras and the computer together.

I chose a different addressing scheme so it could easily be recognised as another part of the network and set up some port forwarding rules so that hosts from the main network could access the camera’s streams. I also needed to setup static IP addressing on all of the cameras to ensure that Blue Iris could always connect to them.

As an extra bonus, I used VLSM (Variable Length Subnet Masking) to only make the network large enough to support the number of devices I required.

Blue Iris

The next step was to setup Blue Iris. First I configured each of the cameras and entered their IP address. Next I setup their sensitivity to motion. I performed this task a number of times, each time walking through the rooms and determining whether the camera was too sensitive or not sensitive enough.

Next I configured the different profiles in Blue Iris. For the moment I just created an armed and disarmed profile. The cameras were set to record all motion in both modes, however alerts were only to be sent to my phone if motion was detected in armed mode. Furthermore, when armed and motion is detected, the recordings made are emailed to myself to get the recording off site.

An Ongoing Project

The system is now working. It will most likely change as I learn more networking and security through my university degree. This will hopefully be an ever evolving system.

Using A 4K Screen On A Computer Without Displayport 1.2 Or HDMI 2.0

My current laptop does not support the latest video standards, display port 1.2 or HDMI 2.0. This means that if I connect it to a 4K display I will be limited to 30Hz. In practice this turns out to be less than ideal as several of the UI elements do not operate in a smooth manner, e.g. the mouse moving across the screen.

Most 4K monitors however, support a function known as picture by picture, or PBP. This mode provides a possible alternative to using the display in 30Hz, by breaking the display in half, using PBP, and using two different cables to supply the two halves with video. This circumnavigates the bandwidth issues with HDMI 1.4 and Display Port by not requiring them to run at 4K. Instead the computer supplies two screens with 1920×2160 @ 60Hz.

This solution is not ideal, at least on Mac OSX, as you cannot have one big window open across your whole screen. However I have not found this to be much of a problem as screens of this size usually have two or more windows open on them at the same time.

To implement this solution you will need to:

  • Ensure that your monitor supports PBP
  • Plug your computer into the monitor using two cables
    • Note: These can be the same interface or different. I have connected the monitor using one HDMI and one Display Port cable, as that’s what I had available on my computer.
  • Turn on Picture By Picture mode
    • This will vary from one monitor to the next
    • Enable Picture By Picture mode on the monitor
      Enable Picture By Picture mode on the monitor
  •  Select the two inputs that you have previously connected to supply a side of the screen
    • Select the inputs that you previously connected to the monitor.
      Select the inputs that you previously connected to the monitor.
  • Use the settings on the computer to place the two screens next to each other
    • Use the display settings to put the two halves of the monitor next to each other.

        Use the display settings to put the two halves of the monitor next to each other


2015 HSC Results

Today I received my 2015 HSC results, which were a combination of my school achievement throughout the year and my exam mark from the October written examinations.

The results were as follows:

  • Standard English 85 Band 5
  • Advanced Maths 85 Band 5
  • Physics 80 Band 5
  • Information And Digital Technology (Networking) 95 Band 6
    • Rank of second in state
  • Software Design And Development 96 Band 6

When these results were combined I was issued an ATAR of 93.3, placing me in the top 7% of the state.

MacBook Pro Retina HDD Replacement

My main computer is a mid 2012 MacBook Pro Retina, making it the first of Apple’s retina laptops. When I bought this laptop, the storage options were limited to the 256GB SSD. This worked well for the first few years, but started to become too small when I started using virtual machines for school work. After working all year with less than 10GB of free space on the hard drive, I finally decided to upgrade it to a larger one.

The hard drive in the MacBook Pro retina is not a standard size, and was designed by Apple especially for the MacBook Pro. Since Apple do not allow you to buy new hard drives from them, I had to look elsewhere. After some looking I found that an American company Other World Computing were selling replacement drives for the MacBook Pro.

After reading several positive reviews and watching the detailed video on how to install the hard drive, I concluded that the OWC Aura 1TB hard drive would work well for my needs. As a bonus the hard drive also came with all the necessary tools to install it in the MacBook Pro and a USB enclosure, so that the old hard drive could be used as an external drive.

Installing the drive was relatively straight forward. The procedure went as follows:

  • Make a backup of all files and settings onto an external drive
  • Remove all of the screws from the bottom cover
    • Many of the screws are different sizes, so it is important to keep track of which hole each screw came out of.
  • Disconnect the battery
  • Remove the screw holding the SSD in
  • Slide the existing SSD out of the socket
  • Slide in the new SSD and replace the screw
  • Put the cover back on the laptop
  • Format the HDD and install the operating system
  • Restore files and settings from the backup

The OWC website has a detailed video of the installation process, which can be found here

After everything was completed, the computer worked just as it had before, only now it had 1TB of storage to play with.

The 1TB drive installed Note: I have partitioned the drive to run a boot camp partition on the mac
The 1TB drive installed
Note: I have partitioned the drive to run a boot camp partition on the Mac


More Air Conditioning

I recently had an extra room added to my house. When it came time to arrange for air conditioning to be installed, it turned out that there was a huge amount of choice on the market now. To ensure we bought the best unit we could I decided to use previous experience and some research to pick one myself.

What Brand

The short answer. Daikin. This was determined on many factors. Firstly our house was originally air conditioned by a 25 year old Daikin. It reliably heated and cooled the room for those 25 years regardless of the outside temperatures. The only reason this unit was replaced was that it’s appearance was no longer suitable for the room as it did really look 25 years old.

Secondly the replacement for this unit was also a Daikin. This unit was a multi-split meaning that two indoor air handlers could be supplied by the one outdoor unit. A 6KW air handler was placed in the kitchen/dining area (where the old Daikin was) and a 7.1KW air handler was placed in the computer/entertainment room. These were both connected to the same 12KW outdoor unit. These two units have performed just as well as the old unit. This unit is also incredibly efficient as it uses a maximum of 2190 watts of electricity to produce the 12KW of heating and cooling power.

Furthermore Daikin, at the time, were the only air conditioning manufacturers producing units with the new R-32 refrigerant (the substance which transports heat in/out of the room). R-32, or Difluoromethane as it is chemically known, is essentially methane except two of the four hydrogen atoms have been replaced with fluorine atoms. This new refrigerant has no ozone depletion factor as well as a higher efficiency. These positive features will lead R32 to become the dominate refrigerant in most domestic and light commercial air conditioning applications. Due to the efficiency of this refrigerant and the system as a whole, it is able to provide 3500 watts of cooling (or heating) for only 860 watts of electrical power consumption.

Due to the success of the existing units and the new R-32 refrigerant, I decided that we should install a Daikin in the new room.

What Size

Ultimately the decision for the sizing of the unit would be left up to the installers. However I could make a rough estimate on the size that would be needed.

Note: In Australia the heating and cooling ability of air conditioners is measured in kilowatts (KW). Kilo essentially means that the 1000’s of watts so 3.5KW would be 3500 watts of cooling or heating power.

From past experience I knew that it would have to be larger then 2.5KW as a similar sized room had a 2.5KW Air conditioner which is only just capable of cooling the room on the hottest days. This other  room also does not have the extreme heat loading experienced by the new room, due to the afternoon sun. After consulting the Daikin catalogue the sizing of the units went 2.5KW, 3.5KW, 4.6KW. Knowing that 2.5KW would be too small and that 4.6KW would probably be too powerful I estimated that the size of the unit would be 3.5KW.

After consulting with the installer it was determined that the size of the unit would indeed be 3.5KW. The indoor unit would be a FTXM35PVM and the outdoor unit would be  a RXM35PVM.


The company doing the installation would be Arctic Air Conditioning.  Luckily they could arrange installation a day after the quote was issued. When it came to the day of installation they were more than happy to let me watch the entire installation from start to finish due to my interest in air conditioning.

The plan was to mount the indoor unit in the middle of the right hand wall, run the refrigerant pipes through the wall and down to underneath the deck where the outdoor unit would be placed.

This is the wall that the air conditioner will be installed on.
This is the wall that the air conditioner will be installed on.
The outdoor unit would be installed underneath the deck here.
The outdoor unit would be installed underneath the deck here.

The total installation went as follows:

  1. Unpacked the indoor and outdoor unit from their boxes
  2. Attached the indoor unit mounting plate to the wall.
  3. Drilled a hole with about a 50mm radius through the wall to pass the refrigerant lines through.
  4. Passed a power and data cable through the hole from the outside (the would eventually be connected to the outdoor unit.)
  5. Attached the indoor unit to the mounting plate and passed the refrigerant lines through the hole.
  6. Attached the pipe cover to the outside wall (all of the pipes and cables would run through this to protect them from the weather and make the installation more visually pleasing.
  7. Created a flared joint between the indoor unit pipes and the length of copper piping that would connect to the outdoor unit.
  8. Placed the outdoor unit on a pre cast cement block and pushed it under the deck.
  9. Installed a power point for the outdoor unit to plug into (more on this further down page)
  10. Created another flare joint to connect the pipes to the outdoor unit.
  11. Connected a vacuum pump to the system to remove all the air out of the pipes and the indoor unit’s coil. (There must be no air in the system, only refrigerant.)
  12. Opened the values on the outdoor unit to allow the refrigerant to circulate around the system. (These systems come pre charged with refrigerant, which is stored in the outdoor unit. When the values are opened it then fills the entire system.)
  13. Performed a test run.
This is the back of the indoor unit before it was installed.
This is the back of the indoor unit before it was installed.
This silver part was the mounting plate for the indoor unit.
This silver part was the mounting plate for the indoor unit.
This is the indoor unit fully installed.
This is the indoor unit fully installed.


The pipe cover running down the wall
The pipe cover running down the wall
A side view of the outdoor unit, under the deck
A side view of the outdoor unit, under the deck
The front view of the outdoor unit.
The front view of the outdoor unit.

Interesting Points

The Outdoor Powerpoint

When electricity was run to this room it was run as a shared circuit. Essentially this meant that the power points and the lights were all on the one circuit and connected to one circuit breaker in the fuse box. However here in Australia air conditioners must be connected to their own circuit breaker so that they can easily be isolated if they require maintenance.

The solution for this was to install an outdoor power point and plug the air conditioner in. This would allow it to be connected to the shared circuit yet still allow it to be legally isolated. As the air conditioner only uses 860 watts of electrical energy at full capacity, a standard power point could be used.

Video Of Air Conditioner Running


Air Conditioner Condenser Fan Replacement

The Problem

Once the weather stated to heat up again my grandparents informed me that their air conditioner had stopped working. After going around to their house and turning on the air conditioning it appeared (from the inside at least) to be working perfectly. The interior fan started working and cold air started to be pumped out of all the vents in the house. After about 30 seconds however the air being pumped out of the vents went back to room temperature. It seemed that the thermostat had switched off the condenser unit.

After navigating the obstacles and getting in a position where i could inspect the condenser unit it became apparent that the fan on the top of the unit was not working. The compressor however could be herd running for short 30 second intervals (after which the compressor was automatically turned off due to high head pressure.)

Possible Causes

My first thoughts were that the fan may have seised up as a result of being exposed to the weather for over 30 years. I removed the cover off the fan and tried rotating it. To my surprise it rotated freely. Evidently that was not the problem.

If the motor spun freely my next thought was that the motor itself was no longer functional. Firstly I tried testing the fan run capacitor, however it appeared to be ok. My next step was to test the motor itself.  To test the motor I removed it from the condenser unit (which turned out to be quite a task) and tested its resistance with a multimeter. The resistance turned out to be incredibly high so high that no current would have been able to flow through the motor. This was therefore the problem and the only thing that could fix the problem was a complete new fan motor. This however still left me with a problem. The old fan assembly was essentially rusted to the old motor and the bracket that held the motor in was somewhat destroyed in the process of removing the motor. What I needed to find was a completely new fan motor and fan assembly.

The Solution

After some looking around on the internet I came across a type of fan commonly fitted to HVAC systems which had everything I needed. It had a new motor and new fan blades. What made it better was that it could be bolted to the top of condenser unit meaning I would not have to try and reconstruct the bracket that held the old motor in place. After measuring the size I ordered one of these fans.

Replacement Fan


The installation was fairly strait forward especially since the old fan had already been removed.

The first step was to take the top off the unit and select an appropriate location for the power cord from the new fan to enter the condenser unit. After finding an appropriate location I drilled a hole and pushed the cord through.

New fan cable being routed into condenser unit.
New fan cable being routed into condenser unit.

The next step was to connect the fan to the appropriate power source in the condenser unit. Luckily there was a wiring diagram printed on the inside of the condenser unit showing where the fan needed to be connected.

The wiring compartment in the condenser unit. Note the white cable is the new fan.
The wiring compartment in the condenser unit. Note the white cable is the new fan and the capacitor to the right of the image is from the old fan motor.

The next step was to put the top back on the condenser unit and screw the fan to the top. Once the fan was screwed to the top and the cables were tidied up the finished product looked like the following:

The finished product.
The finished product.

The only step left was to test the unit and make sure it worked properly. After turning on the unit the whole thing roared back into life which was extra pleasing as the temperature was about 35ºC. After running for about 15 minutes the house was at a cool 22ºC

More pictures
More Pictures
Air Con 2
More Pictures


Video of unit running immediately after installation

Unit running in heat six months after new fan installation

IT HSC Results

On the 5th of November I sat an HSC exam for my Information and Digital Technology. This was a year earlier then I should have sat the exam however I was accelerated through the course allowing me to sit the exam at the end of year 11 instead of year 12.

After waiting for over a month for the results they were released on the 17th of December. My HSC result was a 95 placing me in band 6. Later in the day the rankings were released where I achieved a second in state.

Attached below are the results from the board of studies.

My result from the board of studies.
My result from the board of studies.


My Rank State Wide
My Rank State Wide

Nixie Clock


I have been interested in clocks and lights for as long as I can remember. I have had a variety of main clocks in my bedroom and none of them have been normal. I had a multi coloured LED clock which was good for some time. I then decided to update and went to a Sony “Dream Machine” that had many cool features such as a full colour LCD display and functioned as a photoframe. The software on this device  was rubbish and would constantly crash despite many updates being downloaded from Sony.  After a couple of years of problems and many late mornings due to alarm failure I decided to get a new clock. The problem was where to go next.

Where To Go Next

After the disappointment of the Dream Machine I wanted something that would last while at the same time look cool and tell me the time accurately. At this point I thought back to some clocks I had looked at a long time ago that used the old Neon number tubes (Nixie Tubes) to display the time. A quick google search provided a couple of results and I had a look at all of them. I then found a great website called Nixie Clock Tube Clock Database. the website is a great place to look a nixie clocks from a variety of companies and with a variety of designs. This website also gave good reviews that allowed me to do most of my decision making on their website.

Choosing A Nixie Clock

At first I was overwhelmed by choice. When I started looking i thought that I would have a couple to choose from and the range would not be great. I now had to choose from a variety of characteristics that were available. Some of the characteristics that I had to choose from were:

Type and Size of Tube

There are two main types of tubes to choose from. There are ones that stand vertically and there are others that plug in horizontally. I was not sure which I wanted but came to the conclusion that I wanted one that plugged in horizontally. All of the clocks that had the vertically standing tubes didn’t offer much protection for the tubes and I was worried that I might break one. Most of the clocks with the horizontal tubes however had them well protected and only had the end of the tube exposed.

A vertical nixie tube from
A vertical nixie tube from
Colour Of Backlighting

Another feature on almost all of these nixie clocks is to have a backlight behind or underneath the tubes. For this I wanted a colour that would go well with the orange glow of the tubes. After looking at a few photos I decided that I wanted a blue backlight. There were some clocks that had RGB backlights that the colour could be selected however I just really wanted blue so i didn’t bother with any of these.

Other Various Features

There are many other features that I wanted in my clock such as:

Anti – Cathode Poisoning

This is a neat feature that combats some of the known disadvantages of Nixie Tubes. “Nixie Tubes” are actually 10 neon tubes within one glass enclosure and during normal use microscopic pieces of the cathodes (the numbers) become vaporised and condense elsewhere. In normal neons tubes would just deposit on the inside of the glass and would not become a problem for 30 – 50 years. However when there are multiple cathodes in one enclosure these small pieces of metal can deposit themselves on the other cathodes. If the cathodes are not turned on regularly then this can build up on the seldom used cathodes and stop parts of them from glowing. This is particularly a problem on clocks where some numbers spend hours on. Anti – Cathode poisoning will cycle through the numbers after however many minutes you set it to. This will prevent cathode poisoning and keep the clock looking good for years.

Night Power Down

Because this was going in my bedroom I wanted it to automatically dim the tubes and the backlight at a set time to allow me to sleep. I also wanted to have the tubes return to a normal brightness in the morning.

GPS Time

Some of these nixie clocks can have a GPS receiver that gets super accurate time from GPS signals that will always be right. Setting the time is just a matter of setting the UTC offset. This would be a great feature that would mean that the time was always correct. I had to have this.

Neon Colon Lights

I had noticed on many clocks that the colon lights (the dots between the numbers) were LED’s. The LED’s didn’t seem to match the colour of the neon tubes very well. I therefore wanted a clock that had neon colon lights so that the colours would be exactly the same.


I wanted to build this clock myself because I think that it makes it more special and I would have the ability to replace any components that I didn’t think were good enough with higher quality ones. Another advantage of building the clock as a kit is that if anything went wrong many years in the future I could troubleshoot and replace any basic components that had gone wrong. (Such as resistors or diodes.)

Compatible Tubes

I knew that eventually I would need new tubes to keep this clock going. Some clocks needed a very specific set of tubes while others could support literally 110’s of different tubes.


This was the most basic requirement. The clock had to look good and look well built. I also wanted to choose Nixie Tubes that had a correct looking 5 digit. Many Russian made tubes simply have an upside-down 2 to display a 5. This looks rather odd to me.

The Choice

This list of features produced a small list of possible clocks. In the end it just came down to the one that I liked the most. The choice ended up being the “Black and Wood” nixie clock from nixie kit world. The clock had to be bought in two parts. The kit from nixie kit world and the tubes from Nocrotec.


A couple of year ago I had a model steam roller shipped from Germany using the standard DHL shipping. The tracking was terrible and it took more than six weeks. I didn’t want to go through this again. I emailed nixie kit world and asked them if there was any way to get it here any quicker. They were really helpful and got the clock to me really quickly.


When I opened the box the first thing that I noticed was that everything was packed very well. This gives you an immediate good feeling about the product. The main components such as resistors and diodes came in a big bag that was then split into smaller bags that contained slightly different devices such as different value resistors. The next item was the wooden case. This looked well built and appeared to be cut to size very accurately. The final item was the metal front. This looked to be extremely high quality and was surprising heavy. After quickly placing the metal front on the wooden case the clock looked really good.


The assembly process was relatively easy following the instructions. It was broken down into logical steps and the individual bags for different components made it easy to find the components. During the assembly process I was checking all components to ensure that they were of a relatively high quality. The whole kit was put together in about three hours. It was not hard however having to solder each socket for each pin on each tube and then the diodes to control them and then the leds to go under them took a long time just performing basic soldering.

Here are some pictures of the assembly process

Nixie clock with a few components
Nixie clock with a few components


Nixie clock with some resistors
Nixie clock with some resistors
Nixie clock with high voltage section
Nixie clock with high voltage section


Nixie Clock with one tube in place
Nixie Clock with one tube in place
Nixie Clock with five tubes in place
Nixie Clock with five tubes in place
Nixie Clock with six tubes in place
Nixie Clock with six tubes in place

The Finished Product

When everything was put into its case and then turned on for the first time it looked absolutely amazing. The tubes lit up a bright orange and then the blue backlight came on creating a fantastic looking clock. I cant really explain as well as some pictures could.

The finished Nixie Clock sitting on the table
The finished Nixie Clock sitting on the table

Digital Photo Frame Using Raspberry Pi (With Weather)

I had bought several digital photo frames over the recent years. I was never truly satisfied with any of them. With some, the GUI was hard to use, others the screen was not very good and some just stopped working completely.

After having my Raspberry Pi for a couple of months I realised that I could make my own digital photo frame, using a Raspberry Pi and a monitor of my choice.  This would allow me to use an operating system that I liked and a monitor of my choice that was as big as I liked.

Choosing An Operating System

After a google search, I found massively complicated solutions that didn’t really suit my situation or level of expertise at this moment. I gave up for a few days.In the meantime I discovered Openelec an operating system for the Raspberry Pi (and many other devices) that I then used as a media centre on another Raspberry Pi. After discovering that I could set a slideshow as a screen saver, it gave me the idea to use Openelec on the Raspberry Pi and run the slideshow from the slideshow screensaver. After installing a test version on the Raspberry Pi I realised that having Openelec running on the Raspberry Pi would allow this device to do much more then just show photos. Using features built into the XBMC media centre, it could show the weather, play videos and much more.

Installing Openelec

Openelec can be downloaded as a disk image from the Raspberry Pi Foundations website or their own website. There is another option and that is to use the NOOBS installer that can also be downloaded from the Raspberry Pi foundations website. This installer will allow you to select Openelec from a list and the installer will download and install the operating system automatically.

For more detail on how to install the operating system see my other post Installing OS on Raspberry Pi.

Choosing A Monitor

The monitor is basically your own choice, however it will need a HDMI port to connect to the Pi. The size of my monitor was limited only by the size of the cupboard where it was going to go. After some research, taking into account my size limitation and efficiency, I decided to use a 27 Inch Dell, the S2740L.

Where To Put Your Photos

There are a few options about where to put your photos. The first option, and in my opinion the best option, is to put your photos on a external USB flash drive. This will allow easy transfer of files between your computer and the photoframe. It also allows the storage to increase with future demands.

Another option is to place the photos on the SD card itself. I found this to slow down the Pi slightly. This would also mean that if the storage needed to be updated a new SD card would be required and this would lead to you needing to reinstall the operating system and configure everything again.

The 3rd option is to keep your files on a network drive. This sounds like a good idea however in practice it caused a lot of network traffic and slowed down the whole process. This also led to the screensaver taking about 15 seconds to load.

Setting Up Openelec

After the operating system is installed, the next step is to set up the operating system to work less like a media centre and more like a digital photo frame. You will need a keyboard and/or mouse and have your Pi connected to your display.

Once Openelec has been installed you will be presented with the following screen. If you are using a different skin it may look a little different however the basic principles are the same.

The first XBMC screen after a fresh install
The first XBMC screen after a fresh install

Set Up Network (WIFI)

Note: This will require you to have a compatible USB WIFI adapter plugged into your Pi. 

Firstly navigate to the programs section on the XBMC home screen. Click on the ‘programs’ menu

Once in the programs menu it will show you the list of add-ons that you have. One of them should be called OpenElec configuration. Click on this one.

A new window should open up in a few seconds that will display the OpenElec settings. Navigate to the connections menu on the side of the window. This should display a list of the WIFI connections available near you. Select your one by clicking on it.

A prompt will appear for you to type in your password.

Press Ok. You will then be taken back to the previous menu where you can see the status of your connection. If all goes well this should change to connected. After it is connected return to the home screen.

The first step is to set up the slideshow screen saver.

We are going to use the slideshow screensaver to display the photos for this photoframe.

To do this first move to the ‘system’ tab on the home screen and then go down to the ‘settings’ sub menu. This can be done with the mouse or arrow keys.

XBMC with settings highlighted
XBMC with settings highlighted

In the ‘settings’ menu go to the ‘appearance’ tab.

XBMC with appearance highlighted
XBMC with appearance highlighted

In this menu select the ‘screensaver’ tab

XBMC With screensaver highlighted
XBMC With screensaver highlighted

Once in this menu navigate to the menu ‘screensaver mode’ and click.

XBMC with screensaver mode selected
XBMC with screensaver mode selected

In this menu you want to navigate to the ‘Get More’ button.

XBMC with get more highlighted
XBMC with get more highlighted

Once in the ‘get more’ menu navigate through the list of add-ons until you find one called ‘Slideshow’. Click on the slideshow add-on.

XBMC with slideshow highlighted
XBMC with slideshow highlighted

Another window will open. ‘Click install’.

XBMC with slideshow install highlighted
XBMC with slideshow install highlighted

XBMC will now download the add-on and install it for you. After the add-on is installed you will be returned to the add-ons selection menu. There should be writing next to the slideshow add-on that states enabled.

XBMC with slideshow enabled
XBMC with slideshow enabled

Press escape. This will return you to the screensaver screen, select the screensaver mode again.

XBMC with screensaver mode selected
XBMC with screensaver mode selected

Once the screensaver options windows is open go down and select the slideshow add-on that you just installed.

XBMC with slideshow selected
XBMC with slideshow selected

You will be taken back to the main screen saver menu. You will notice that next to the ‘screen saver mode’ menu it will now say ‘slideshow’.

XBMC with slideshow selected
XBMC with slideshow selected

The next step is to select the settings menu on the same screen.

XBMC with settings selected
XBMC with settings selected

A new window will open. Under the basic tab you want to set the ‘source of slideshow images’ to “Image Folder”. Set the folder to the location of where your photos are stored. Under the ‘amount of seconds to display each image’ set the time in seconds that you want the pictured to be displayed for. Dim level should be set at 100%. You can set the effect to any setting you want, however I like the default Pan and Zoom.  After being setup, mine looks like the picture below.

Slideshow with basic configured
Slideshow with basic configured

You can have a look at the additional and advanced menus however I didn’t need to change any of them. Click Ok when you are done.  Note: If you don’t press ok your changes will not be saved.

XBMC with screensaver settings. Ok highlighted
XBMC with screensaver settings. Ok highlighted

In the main screensaver menu you can now select how long the machine is idle for before starting the screensaver. I have mine set to one minute.

Main screensaver menu
Main screensaver menu

You can now press ‘escape’ until you arrive back at the home menu again.

At this point you should have a working digital photo frame powered by the Raspberry Pi. Just wait 1 minute for the screensaver to start.  If this is all you want then you can stop here however, there are many other features that you can enable to make this photo frame even better.

Configuring Weather

Configuring Location

Another feature of my photoframe that can easily be configured is the ability to have the weather automatically displayed when the photo frame starts and when it is brought back from the screensaver.

From the home screen navigate to the ‘system’ tab and select the submenu ‘settings’.

XBMC with settings highlighted
XBMC with settings highlighted

Navigate to the ‘weather’ tab inside the settings menu

XMBC settings with weather highlighted
XMBC settings with weather highlighted

You will be presented with the following window. The default weather provider is “weather underground” which is quite good and covers a large amount of places. Others can be selected, expanding the capabilities of the weather feature, however this will be covered in another of my posts later. At the moment you want to navigate to the settings tab.

XBMC weather settings
XBMC weather settings

When you open this menu you will want to select the ‘enable’ button and then go down and click on location 1.

XBMC weather settings open
XBMC weather settings open

This will bring up a window with a place for you to enter your current city or at least a big city near you. For example, I am going to enter Sydney. Press ‘done’ on the side panel when you are finished.

Sydney entered into weather prompt
Sydney entered into weather prompt

Depending on your internet connection and how many results are returned, it may take a couple of seconds until the following window is displayed. Select the city that you want from the list. For this example I am going to select Sydney Australia.

Weather with Sydney Australia Selected
Weather with Sydney Australia Selected

You should be returned to the main “weather underground” settings screen and your location should be in the location 1 slot. If this is correct press Ok.

Weather underground with sydney in location 1
Weather underground with sydney in location 1

You can now press escape and return to the home screen. Select the weather tab to check that it works.

XBMC home screen with weather selected
XBMC home screen with weather selected

If everything is working the following screen should display the weather for your location and look something like the following picture.

XBMC displaying weather
XBMC displaying weather
Configuring Weather To Start By Default

After you have the weather working correctly it is now time to configure XBMC to automatically open the weather tab.

To do this first go to the ‘system’ tab on the home screen and then select the ‘settings’ sub menu.

XBMC with settings highlighted
XBMC with settings highlighted

Next select ‘appearance’ from the side menu.

XBMC with appearance selected
XBMC with appearance selected

Stay on the ‘skin’ tab and navigate to the menu called ‘startup window’. At the moment this will say home window.

Appearance settings with skin and startup window highlighted
Appearance settings with skin and startup window highlighted

Using the arrows change the item listed from ‘home window’ to ‘weather’.

XBMC with startup window set to weather
XBMC with startup window set to weather

Restart the Raspberry Pi. When the Raspberry Pi boots up again it will display the weather until it has sat idle for one minute (or however long you set) before automatically starting the slideshow. Viewing the weather again is as simple as moving the mouse or pressing a button on the keyboard.

After my photo frame was working correctly I removed the mouse and left the keyboard connected. The keyboard now lives in the drawer below the photo frame so that it is just a simple press of the space bar to bring up the weather. Below are some photos of the finished product.

This photo frame will be getting better when I have time to work on it and any improvements will be posted in this blog.

Photoframe Front View
Photoframe Front View
Photoframe With Keyboard
Photoframe With Keyboard
Photoframe With Weather
Photoframe With Weather
Photoframe Picture Of Raspberry Pi
Photoframe Picture Of Raspberry Pi

Installing OS On Raspberry Pi

I bought my first Raspberry Pi about a year ago and since then I have used them for a variety of different tasks.  However, before the Raspberry Pi is good for anything at all, it must have a operating system installed on the SD card. When I did this for the first time, the instructions were a bit sketchy and the installers were much harder to use. The good news is it is a lot easier now.

Choosing The Installer Or Image

The first step in this process is to download the installer or the operating system image. These are the two options that you have and either of them are will work, however the NOOBS installer will almost always be easier.

The NOOBS installer is useful for almost everything. It allows you to select from a list of operating systems. There are two types of the NOOBS installers. One has all the operating systems pre downloaded so that they can be installed without a network connection. The other is a light version that will download the operating systems using a network connection. Once selected, your operating systems will be installed. if you have chosen the light version, it will have to download your operating systems before they can be installed. In my opinion, this is the best option.

The second option is to image the SD card yourself. For this you will need to download the disk image and an imaging program. This should only be used if you are trying to install an operating system that the NOOBS installer does not offer.

Operating Systems

There are countless operating systems for the Raspberry Pi. (A quick google search will reveal many) I have only ever needed to use two of the operating systems in any depth and therefore those are the only ones I can comment on.

Rasbian – The default operating system. This is what most Raspberry Pi projects are based around. It is best thought of as a lightweight debian operating system for the Raspberry Pi. It offers a normal linux command line and a very debian like looking desktop environment. This operating systems can also take advantage of the vast debian package library which can be accessed through the apt-get command.

OpenElec – Essentially XBMC for the Raspberry Pi. This is just a lightweight linux operating system that boots straight to XBMC. Once XBMC is running it also provides a graphical interface for configuring a network connection and any other features that would usually be configured by the operating system running XBMC on a regular computer.

Downloading NOOBS or OS Image

The NOOBS installer and the main operating system images (along with some good documentation) can be downloaded from the Raspberry Pi website. If possible, it is helpful to use the torrent downloads for the images because this will reduce the network traffic across the Raspberry Pi foundation servers. Simply click on the download link for whatever you want to download. Everything will come as a .zip. When the NOOBS installer is unzipped it will create a folder called NOOVS_lite_v1_3_4. Inside that folder will be the necessary files. When the operating system images are unzipped it will just leave behind the image.

Screenshot of raspberry pi downloads page
Screenshot of raspberry pi downloads page
ScreenShot Of The Downloaded NOOBS
ScreenShot Of The Downloaded NOOBS
Screenshot Of NOOBS installer folder after unzipping
Screenshot Of NOOBS installer folder after unzipping
Contents Of The NOOBS Folder
Contents Of The NOOBS Folder

Flashing The SD Card

The next step after everything has been downloaded is actually putting the NOOBS installer or the image on the SD card. First the NOOBS installer.

  1. Insert the SD card into your computer
  2. Format the SD card to ensure that there is nothing else on the card. This can be done using disk utility on a mac and windows explorer on a PC.
    Formatting SD Card On Mac
    Formatting SD Card On Mac


  3. Simply drag and drop the files and folders from the NOOBS folder onto the SD card
  4. Plug the SD card into raspberry pi and your done. (It really is that simple.)
  5. Note: These steps are the same for both windows and Mac

Now for the operating system image For this step you are going to need some sort of disk imaging tool. I’m a Mac user however for this step I recommend using a windows machine because I have found no reliable way of doing this on a Mac. For windows I used Win 32 Disk Imager. Open Win 32 Disk Imager The computer will ask you to click yes as it has to run as administrator

Win 32 Disk imager asking for permission to run as administrator
Win 32 Disk imager asking for permission to run as administrator

Using the small select folder button select the disk image that you want to flash to the SD card.

Win 32 Disk Imager with folder button circled
The button to press is circled

Now select your SD card from the device drop down menu. Note: Make sure that it is the right device as everything on it is going to be deleted.

Win 32 Disk Imager with devices circled
The devices section is circled

After these two are selected you are ready to hit write. Check one more time that the destination is correct. You don’t want to erase your a different device.

Win 32 Disk Imager with write circled
Click Write

The disk imager will now “burn” the image file to the SD card Once this has finished you can eject the SD card and you are ready to put it into your raspberry pi and turn it on.

Installing On Raspberry Pi

Once the Raspberry Pi has been turned on you should see a multi coloured screen and then a screen with a raspberry in the middle of it similar to the following two pictures.

Raspberry Pi Rainbow Screen
Raspberry Pi Rainbow Screen
Raspberry Pi Installer Screen
Raspberry Pi Installer Screen

You will now be presented with a screen like the following. The picture of the SD card next to each operating systems means that it has already been downloaded and can be installed without a network connection. If you downloaded the lite NOOBS installer then there will be a different symbol next to the operating systems that the pi will have to download the operating systems installers once the installer is started.

List of operating systems for raspberry pi
List of operating systems for raspberry pi

You can now go through and select one or more operating systems to be installed by selecting the checkboxes on the left hand side of the operating system. For this example I am going to select Raspbian, OpenElec and Pidora. Click install when you have your operating systems selected.

NOOBS installer with raspbian, OpenElec and Pidora selected
NOOBS installer with raspbian, OpenElec and Pidora selected

You will be notified that any data on this SD card will be erased. Click yes.

NOOBS installer asking for permission to continue
NOOBS installer asking for permission to continue

You will now be presented with a series of screens starting with the following that will tell you a small about the operating systems you have selected.  It will also tell you about the progress of your installation.

Operating systems being installed
Operating systems being installed

You will then be presented with a dialogue box that tells you that the Os(es) have been successfully installed.

Raspberry Pi OS(s) successfully installed
Raspberry Pi OS(s) successfully installed

After you click Ok you will be presented with a screen listing the operating systems installed on your SD card. Simply click on the one that you want to boot. You have now successfully installed an operating system on the SD card.

Raspberry Pi boot options
Raspberry Pi boot options after installation